oracle

Scripts: Monitor Tablespace space growth

January 10, 2013 maintain, oracle No comments

这个脚本可以监控tablespace 空间增长趋势,并且邮件通知到相关domain– 根据TOAD SPACE MANAGEMENT 修改

创建schema,tablespace,table:

create tablespace toad '+ARCH/data/tbs_ts[......]
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Block split and entry reorder

December 12, 2012 Internals, oracle No comments

今天跟研发的同学讨论到了这个问题,index block split过程中涉及到的重新排序问题.

SQL> create table idx_split (a number, b varchar2(1446), c date);   
 
Table created
 

SQ[......]
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Scripts: dbms_backup_restore modify dbid and db_name

December 5, 2012 Internals, oracle 1 comment

Scripts:dbms_backup_restore_dbid

eg:

Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Par[......]
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Oracle Bind Graduation 测试

November 28, 2012 Internals, oracle No comments

最近team 讨论 Bind Graduation 比较激烈,详细可以见上一篇文章,基于Bind Graduation 做了以下测试：

主要目的：

测试基于OCI JDBC 等接口的 Bind Graduation行为.针对目前Bind Graduation的行为,以及11.2.0.[……]

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Can not purge obsolete cursor in 11.2.0.3

November 28, 2012 11g, maintain, oracle No comments

11.2.0.3中Oracle引入了_cursor_obsolete_threshold隐藏参数，默认为100，表示一个parent cursor最多可以有100个child cursor;如果SQL需要第101个child cursor,则将该parent cursor and its 100 c[……]

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[转] ASM Handling Block Corruptions

November 25, 2012 oracle, RAC No comments

Some excellent experiment From Honcho

为了保护disks 上的数据，Oracle ASM 对disk groups 有3种冗余方式:
（1）external redundancy 表示Oracle不帮你管理镜像，功能由外部存储系统实现，比如通过RAID技[……]

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Oracle Direct NFS Performance

November 23, 2012 11g, Architect, oracle, software 1 comment

在Oracle 11g中引入了Direct Network File System(Oracle Direct NFS)的新特性，通过一个打包在Oracle内核中的NFS client来提高使用NFS时的性能，DNFS同样适用于RAC等高可用场景。

DIRECT NFS CLIENT OV[……]

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Logon Storm

November 16, 2012 network, oracle No comments

A Logon storm is a sudden spike in the number of client connection requests. Logon storms can occur due to a variety of factors. They could be malic[……]

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Incremental Statistics for Partitioned Tables in 11g

November 8, 2012 11g, oracle No comments

这篇文档是我们前leader wwf 写的分析文档,指出了incremental statistic针对partition table 的一些用法,并且指出了一些bug,看不了slideshare的TX可以直接下载Inc_Stat_For_PT.doc

Exadata X2-2 Hang死一例

November 3, 2012 Exadata, oracle No comments

Exadata不是万能的 一直觉得xd DB端的服务器太差,但是oracle总是可以理直气壮的说我们卖的不是硬件是软件.垃圾SQL压死Exadata还是很容易的

系统为X2-2 Quarter rack Red Hat Enterprise Linux Server release 5.7 ([......]
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